VocalTec Communications Ltd. Chief Executive Officer Ido Gur said he needed to sell 15 of the Israeli company’s 22 inventions to raise money to market its main Internet phone software. Irvine Sensors Corp., whose infrared camera technology is used by the U.S. military, and TurfTrax Plc, a U.K. owner of patents for monitoring horseraces, are also selling or considering a sale of rights to stem a slump in revenue.

“I needed the money,” said Gur, 40, who agreed to become CEO on condition that VocalTec, which reported $5.8 million in 2007 revenue, would dispose of its consumer phone patents to focus on sales to clients such as Deutsche Telekom AG. “I would be able to recover VocalTec only when I had cash in hand.”

Developers who once imagined spending years to build businesses that would create multiple products or tap many markets now find they need to scale back their ambitions. Applications for intellectual property transfers in the U.S. climbed 20 percent in the second half of 2008 to 199,699 from a year earlier, data compiled by the Patent and Trademark Office show. In the U.K., the number of requests rose 41 percent.

“They can essentially raise cash without diluting existing investors,” said Andrew Ramer, managing director of the transaction practice at Ocean Tomo LLC, a Chicago-based merchant bank that auctions intellectual property collections for smaller businesses and individuals. “Selling their patents and keeping a license back allows companies to have their cake and eat it, too.”